<!DOCTYPE html>
<html lang="zh-CN">
    <head>
        <meta charset="UTF-8" />
        <title>11_定位-绝对定位-基本使用3</title>
        <style>
            #d1 {
                position: relative;
                width: 500px;
                height: 500px;
                border: 30px solid red;
            }

            #d2 {
                width: 300px;
                height: 300px;
                border: 30px solid green;
            }

            #d3 {
                position: absolute;
                left: 0;
                top: 0;
                width: 100px;
                height: 100px;
                border: 30px solid aqua;
            }



        </style>
    </head>
    <body>
        <div id="d1">
            <div id="d2">
                <div id="d3"></div>
            </div>
        </div>
    </body>
</html>